Abrasive holder



Jan. 3, 1956 D. D. soccoLl 2,729,037

ABRASIVE HOLDER Filed Oct. 19, 1953 2 SheetsSheet 1 1 2,729,037 ABRAS'IVE Hi'JIjDE'R Dom D. Soccoli, New Britain, Conn. Ap licatien october 19, 1953, Serial No. 386,748 1 Claim. (Cl. 51-197) This invention relates to new and useful improvements in an abrading, bu'ifing or polishing tool and is directed more particularly to the provision of improved means for retaining a sheeting of sandpaper, emery, Carborundum or the like, or a padding of steel wool or polishing or bufling material such as cloth or the like, or similar abrasive, bufling or polishing materials in the desired operating positions for the abrading, buffing or polishing actions.

It is another object of the invention to provide a holding means comprising relatively stationary and movable interengageable clamping elements or members 'whereby the abrading or buffing or polishing material may be retained under tension and positively locked against accidental displacement when in operational use.

A further object of the invention is to provide a resilient cushion or pad member having a substantially curving convex shaped surface against which the abra'ding, buffing or polishing material may be brought into close alliance for the elastic or yielding action. The cushion or paid member and the related abradi'ng, bu'ffing or polishing material are capable of being readily depressed or flattened when in operational use and of returning to their original convex shape when released firomJ-the depressed or flattened operating position adjacent the work.

The novel apparatus of the invention is characterized by a gripping or holding means whereby a sheet of an abrasive, buffing or polishing material may be positively and securely gripped and retained during manual and/or mechanical manipulation of the same, which means is preferably rotated in sucha manner that an intermittent abrading, buffing or polishing action is attained.

The device of this invention, or a plurality thereof, 'can be applied to a work piece for the abrading, smoothing, reducing, finishing, buffing and/or polishing of the surface of the same, with the advantage that the operation can be viewed when same is/are rotated at sufiiciently rapid rates or speed, a function heretofore impossible with rotary disc type sanders, polishers and similar devices known in the art.

It is a still further object of the invention to provide a holding or retaining means for the sheeting of the abrasive material, the efficient functioning of which improves as pressure on the device is increased during operational use, the sheeting, being held relative to the holding means partially through its own abrasive qualities as same is depressed and urged toward elements of the holding member under manual or mechanical manipulation.

It is another object to provide means of novel form whereby a sheet of abrasive or polishing material may be readily applied to or removed from the structure'with dispatch, said means permitting the application or removal more expeditiously -than h'as'heretofore been possible in the case of any known prior art devices.

Exceptionally fine or high quality finishes may be obtained with the device of the invention due to the fact that varying and graduated pressures may be more equitably applied. Particularly pertinent is the fact that less pressure may be applied at certain areas of the abrading devices (for instance, the outer end portions of. the devices which upon rotation travel at the highest rates of speed) and more pressure may be applied at certain other areas of the devices (for instance, the inner end portions of the devices which upon rotation travel at the lowest rates of speed). Pertinent too is the fac't that at these areas of lowest rotatin speeds, the abrading or polishing action is the greatest.

United States Patent 2,729,03'? Patented Jan. 3, 1956 ice 2 It is to be additionally emphasized that the device or this invention herein to be described ofie'r's certain distinct advantages over the disc "type of sander or polisher, among which is the fact that in this latter type, the provision of a an opening located centrally of the disc is normally necessitate'd in order that the sheeting may be held relative to the structure. It will be appreciated that in the device of this invention, the need for such a central opening is obviated.

While this invention is illustrated as embodying a device adapted for supporting an abrasive or polishing element, it will be readily understood that the holder as illustrated may be em loyed for other similar or related purposes and may be embodied in combination with other mechanism as will occur to those skilled in the art. This invention finds a wide field of utility for purposes, such as buffing and/or polishing, other than the specific ones herein disclosed. v

The above cited objects are accomplished by means of such structure and relative arrangement of parts thereof, as will fully appear by a perusal of the description below and by various specific features which will be hereinafter set forth and fully described and referred to in conjunc tion with the accompanying drawings wherein:

Fig. 1 is a top plan View of one form of the device of the invention;

7 Fig. 2 is a bottom plan view of the device shown in Fig. l;

Figs. :3 and 4 are end and side elevational views respectively of thedevice shown in Figs. land 2 Fig. 3 is a sectional 'el'e'vational view of a modified form of the device of the invention;

Fig. 6 is a bottom plan view of still another modified form of the device ot' the invention;

7 is a sectional 'eleva'tio'nal View of a modified form of the cushion member of the invention;

fig. is a bottom plan view of another modified form or the device or the invention; and

Fig. 9 is a side elevaiional 'view of the device shown in Fig. 8.

in the accompanyihgdrawings, 1 have illustrated several complete examples of physical embodiments of the invention. it will be understood, however, that changes and alterations are contemplated and may be tirade in these mechanical structures, within the scope of the appended claim without departing from the broad principles of this invention.

I In the following description and claim, various details will be identified by specific names for convenience. These names, however, are; intended to be as generic in their application as the art will permit.

Referring now to the drawings more in detail, I have shown a holder which is generally indicated by the numetal iii and which consists of a single rectangular piece or metal. It comprises a substantially rectangular shaped body portion consisting of a rigid fiat base or support 12.

Opposite side portions of the base 12 are turned downwardly so as to provide outwardly extending spaced opposite angular extensions or lips 14, as shown.

Disposed centrally of the base 12 and extending upwardly therefrom is a spindle or shank 16 which may be fixed to the holder lilas by nuts and washers 18 and 2'6 respectively in the usual manner or in any other conventional manner, all to the end that the spindle 16 may be engaged by some motor driven accessory, such as a drill press, hand drill, or the like for the purpose of imparting a rotating. motion to member 10 and other components associated therewith. That is to say, the spindle 16 is preferably of a type adapted to be mov ably supported and manually manipulated to various operating positions, the driving means not being illustrated herein as it will be understood to be of one of the conventional forms and does not form a part of this invention.

A cushion or pad member 3% is made of rubber or similar material having flexing or yielding characteristics. The member 30 is normally substantially fiat in configuration but may be bowed or flexed into a convex shape whereby its opposite side portions may be received within the inner sides of the lips 14 and 14.

In assembly, upon the release of the member 30 from the aforementioned bowed or flexed position, same may be snapped into a locked position relative to the member 10, such as shown in Fig. 3. In this manner, the member 30 assumes the generally convex shape shown and, of course, is detachably coupled to the member 10.

In the assembly of the device, the outermost surface of the member 3%) is covered with a sheet of sandpaper 40 or similar abrasive or polishing material in sheet or web form, all as aforementioned. That is, the abrasive material employed may be sandpaper, emery, Carborundum or the like depending on the requirements of the work and the choice of the operator.

If desired, a pad or webbing of steel wool may be substituted for the sandpaper 40 for specific purposes and uses as may be required. Conceivably, a buffing or polishing pad or cloth of appropriate dimensions may be substituted therefor for other specific purposes.

The sheeting or web 40 is stretched over and adjacent the member 30 and is clamped to the body member by means of the aforementioned gripping action between the respective lip 14 and the side edge of the portion 12 at each side of the device.

If desired, said sheeting 40 may be of such width as to permit the turning inwardly of the opposite side edges over the respective ends of the member 30. That is to say, each side edge of the member 40 may be lapped over the respective side edge of the member so as to insure a tighter fit and firmer grip between the parts.

Further and if desired, the sheeting 40 may be of such length as to extend outwardly at one or both of the end edges of the member 30, all for purposes as will hereinafter he explained.

The holder 10 is substantially non-yielding when subjected to the operating stresses and pressures under which the device is designed to be used but the cushion or pad member 30 is adapted to be substantially depressed or flattened as the same is subjected thereto and, of course, the sheeting or webbing 40 conforms to the general contour thereof accordingly.

As aforesaid, as these stresses and/or pressures are exerted, the gripping or clamping engagement between the lips 14 and the outer side edges of the cushion member 30 is increased, the opposite side edges of the member 30 being forced outwardly in diverging relation into the \-shaped pockets formed between the lips 14 and the member .12, the sheeting or webbing 40 being more tightly clamped as this function takes place.

Upon rotation of the device through the spindle 16 and as same is brought to bear against the work piece, the pressure between the flattened or depressed member 30 and the holder 10 is increased whereby the sheeting 40 is more securely held in place.

It is contemplated that in the normal employment of the device, the free end edges of the member 30 will be brought into operating contact with the work piece before the central body portion thereof. To this end, the thickness of member 30 is varied between a relatively thickened midsection or central body portion and opposite end sec tions where the same gradually diminish relatively thin feather end edges. Thus the thickness tapers from the thicker midsection outwardly in opposite directions toward the thin feather edges. It will be appreciated also that the midsection has a greater rigidity than the relatively flexible feather edges at the opposite ends.

The feather edges may be disposed closely adjacent or slightly beyond the respective end edge of the base plate member 12, all as may be desired. Where the feather edge is disposed beyond the respective end edge of member 12, the flexibility at the end edges is increased, same not being restricted in its movements by the lips 14.

The cushion member 30, being so tapered, is better adapted to provide the desideratum in cushioning action, the thin feather edge portion being more resilient and yielding than the relatively more rigid central body portion.

As aforesaid, these outer end edges are normally the first to be brought into contact with the work as the abrading action is commenced. Tapered slots 32 may be provided which extend inwardly from each of the opposite end edges of the member 30, all for purposes of facilitating the depressive action thereof as the member 39 is pressed against the work. The slotted means permits the easy assumption of the flattened or depressed shape aforementioned, the tendency of the members 30 and 40 to fold, crease, or buckle in the area of initial contact being appreciably lessened thereby.

The member 10 being more or less rectangular shape, a so-called intermittent abrading or polishing action results as same is rotated. That is, as one end edge portion of the adjacent members 30 and 40 is rotated over the work piece, it is followed by a momentary interval before the opposite end edge portion is rotated thereover. Thus an intermittent action, as contrasted with a continuous action is attained and as a result thereof, the cuttings or other materials being removed from the surface of the work piece are more easily expelled. They do not pile up as in the case of flat disc type actions where the abrading or polishing force is continuous and non-intermittent.

As each of the end edges completes its so-called pass over the surface being worked upon, the yielding action of the cushion member 30 urges the sheeting 40 to belly outwardly upon release of the pressure so as to expel the cuttings or dust. The debris or waste such as the paint or similar soft material being removed is thus permitted to be worked out from under the sheets 40 for the expulsion and elimination thereof instead of being ground into the same so as to fill the surface of the sheets thereby reducing the effectiveness thereof.

It is further to be explained that the device minimizes the likelihood of gouging or overgrinding as the holder is rocked or translated across the work and manipulated to bring the abrasive material into contact with relatively narrow recessed or retracted portions of work.

That is to say, the exertion of pressure upon the device permits the yieldable member 30 to conform in shape to the surface being abraded or polished and, of course, the sheet of abrading material will also be permitted to conform to the surface with which it is in contact.

This characteristic of resiliency is further noted when and as the pressure is relieved whereat the members 30 and 40 immediately are returned to their original and normal convex positions.

One of the principal advantages of the structure over prior art devices is that, when butting, it is possible to obtain uniform pressure upon irregular surfaces, the cushion 30 and sheeting 40 being self-cushioning and selfconforming when applied to the work being operated on.

The tapering cross section of the rubber member 30 gives a high degree of flexibility to the device. The relatively solid central polishing or abrading sections and the relatively flexible outer polishing or abrading sections have sufficient support to allow the abrading material to cut into the material being worked upon while flexing as needed in restricted areas.

Furthermore, by the generally rectangular configuration of the device as contrasted with the common and well known circular configuration of prior art devices, the mushrooming effect or buckling action common to circular or disc type abrasive holders is likewise eliminated.

In use, if desired, the sheeting 40 may be removed from its clamped position and reinserted after turning the said sheeting in a 90 angle so that the edges thereof formerly at the opposite ends of the structure are thereafter disposed at the opposite sides thereof in the clamped position between the members 30 and the lips 14 and 14. That is, by shifting the sheeting relative to the holder, a fresh abrasive surface may be presented to the work when desired or necessary. In this manner, the life of the sheeting can obviously be increased, thereby effecting great economies in materials.

Also, as aforesaid, the length of the sheeting or webbing 40 from end to end thereof may be greater than the length of the body member so as to extend beyond the ends thereof a predetermined distance at each end. With the device in the assembled or operating position and with the overhanging length of sheet material 40 at each end thereof, certain so-called wing cut abrading and cutting operations may be performed therewith. Said operations cannot be performed as easily with a disc type of device. For example, it may be used in contours, grooves and other uneven work surfaces as distinguished from the normally fiat surfaces with particularly satisfactory results.

In the modification shown in Fig. 5, I have shown a holder comprising a flat base 12 having angularly disposed lips 14' and 14 depending therefrom at opposite sides thereof, similar to the construction in Figs. 1-4.

An elastic cushion member 30', similar to the member 30 is engaged between the lips 14 and 14' in the manner heretofore described.

Additionally, a secondary elastic cushion member 31 comprising a double walled member having a sealed and inflated pocket 33 therebetween is disposed adjacent the outer surface of the member 30' and may conceivably be integral therewith.

Also conceivably, an inflatable cushion member 31' of appropriate size could be substituted for the member 30 altogether.

The pocket 33 may be inflated with air or the like, all to the end that improved qualities and characteristics of resiliency are attained therewith.

The abrasive or polishing sheet 40 is associated with this structure in the manner heretofore described and the secondary cushion member 31' is held between the members 30' and 40 all to the end that increased resiliency is obtained. Compression of the members 30 and 31' in operation results in the face of the sheeting 40' being brought into closer alliance therewith.

As illustrative of still another form of the invention, a plurality of the devices 10, shown in Fig. 1, may be secured in any suitable manner to a circular disc or plate 50 in a circular manner, the said plate 50 being engaged and rotated by means of a drill or the like through a centrally disposed upwardly extending spindle 52, all to the end that the abrading of larger work surfaces can be more easily accomplished.

In Fig. 7, a modified form of the cushion member 30 above described may be employed. The cushion member 130 is shown as having a normal curvature slightly less than the normal curvature of member 30. That is, the member 130 is a purposely molded form having a relatively fiat central surface 131 and relatively thinned areas 132 connecting the flat surface 131 and the adjacent side edges 133. Being so formed, the flexure along the axes of the thinned areas 132 is more easy of attainment and the tendency of the member to bend in its midsection is lessened.

In Figs. 8 and 9, I have shown another modified form of my invention.

A plurality of the holding devices, each generally designated by the numeral 210 may be secured in any suitable manner to an annular disc or plate 250.

It will be observed that in this form, the holders are more or less tapered outwardly from one end to the other. That is, the width of each holder is generally less at one end than at the other end of the device.

Outwardly extending lips 214 are provided as are the cushion members 230 which are held relative thereto in the aforementioned manner.

The abrasive or polishing material in sheeting form 240 is held relative thereto in the manner heretofore described.

The plate 250 is engaged and rotated by some mechanical means through a centrally disposed upwardly extending spindle 252 which may be provided with a head 254 and may be secured to the assembly as by a nut 256 or the like.

If desired, the spindle may be riveted or bolted to the disc and a centrally located boss integral with the disc may be provided for this purpose. Or the spindle may be secured to the disc in other conventional ways.

Openings 260 through the plate 250 and between the devices 210 permit visual inspection of the work as same is being abraded or polished.

The devices 210 comprising the holders heretofore described are secured to the lower face of the disc 250 in circular series with spaces therebetween. The cushion members and the holders, in this modification, will be observed to be generally pie or wedge shaped though it will be understood that they may be generally rectangular in shape if desired.

The present embodiments of the invention are to be considered in all respects merely as being illustrative and not as restrictive, the scope of the invention being indicated by the appended claim rather than by the foregoing description, and all modifications and variations as fall within the meaning and purview and range of equivalency of the appended claim are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the United States is:

An abrading tool adapted for rotation at high speed by an electric drill or the like having a chuck comprising in combination, a substantially fiat and rigid sheet metal holder having longitudinal relatively narrow lip portions at opposite edges thereof depending downwardly therefrom in relatively converging relation, an elongated spindle extending upwardly from said holder adapted for engagement by a chuck, a pad member formed from yieldable and resilient material and a sheet of abrasive material overlying the outer face thereof, opposite side edge portions of said sheet and of said pad member disposed in abutting relation with adjacent inner portions of said holder and lips, said pad member and sheet having a relatively greater transverse width than the distance between said lips whereby portions of said pad and sheet extend outwardly from between said lips in curving convex relation, opposite end portions of said pad member between opposite sides thereof increasing in thickness inwardly from end extremities thereof to a relatively thicker central portion intermediate said opposite end portions whereby said pad member is relatively more yieldable at opposite end portions thereof than at said central intermediate portion.

References Cited in the file of this patent UNITED STATES PATENTS 133,350 Ball Nov. 26, 1872 505,644 Webster Sept. 26, 1893 528,024 Perry Oct. 23, 1894 973,912 Buck Oct. 25, 1910 1,944,302 Ricks et al Ian. 23, 1934 1,945,823 Rasch et al. Feb. 6, 1934 2,205,606 Storer June 25, 1940 2,227,588 Kemp Jan. 7, 1941 2,229,250 McRae et al. Jan. 21, 1941 2,332,676 Stetler Oct. 26, 1943 2,493,505 Schueller Jan. 3, 1950 FOREIGN PATENTS 249,656 Great Britain Apr. 1, 1926 

